Experiments and theoretical analyses are conducted in a residential building in Changzhou to study indoor PM_2.5 concentrations by establishing a combined parameter model. An alternative method for predicting the particle deposition rate and penetration coefficient is proposed, and its accuracy is tested and verified by experiments using time-dependent concentrations and air exchange rate measurements. The predicted PM_2.5 penetration coefficient increased from 0.70 to 0.88 when the air exchange rates were varied from 0.2 h⁻¹ to 0.5 h⁻¹. In addition, outdoor sources of PM_2.5 dominantly contributed approximately 90% to 98% to the indoor concentrations for both mechanically and naturally ventilated structures. Finally, a mathematical model for predicting the indoor concentration is presented using a mass balance equation, which estimates the parameter values in the building. The indoor PM_2.5 concentrations ranged from 40 to 46 µg/m³ by using a fresh air system with 82% filtration efficiency, while those by using open windows for natural ventilation ranged from 105 to 118 µg/m³ when the outdoor PM_2.5 concentration ranged from 115 to 137 µg/m³. The results of this study can be used to estimate the indoor particle level.

Practical application: By applying the ventilation criteria for acceptable indoor air quality in ASHRAE Standard 62.1, the indoor PM_2.5 monitoring results show serious pollution in dwellings in 2018. More dwellings are expected to maintain a clean indoor environment in the future. Thus, it is crucial to consider the indoor PM_2.5 pollution risk in the building design to prevent the possible consequences of unsafe high indoor concentrations. The use of this prediction model, as discussed in this article, will provide further information on the influence of the particle deposition rate (K) and penetration coefficient (P) on indoor PM_2.5 concentrations.

通过在常州某住宅楼中进行实验和理论分析，通过建立组合参数模型来研究室内PM _2.5浓度。提出了另一种预测颗粒沉积速率和渗透系数的方法，并通过使用随时间变化的浓度和空气交换速率测量的实验来测试和验证其准确性。当空气交换速率从0.2 h ^-1变为0.5 h ^-1时，预测的PM _2.5渗透系数从0.70增加到0.88 。此外，PM _2.5的室外来源机械和自然通风结构的室内浓度主要占室内浓度的大约90％至98％。最后，使用质量平衡方程式给出了用于预测室内浓度的数学模型，该方程式可估算建筑物中的参数值。通过使用具有82％过滤效率的新鲜空气系统，室内PM _2.5的浓度范围为40至46 µg / m ³，而当室外PM _2.5浓度的情况下，使用开窗进行自然通风的室内PM _2.5浓度范围为105至118 µg / m ³。范围从115到137 µg / m ³。这项研究的结果可用于估算室内颗粒水平。

实际应用：通过应用ASHRAE标准62.1中可接受的室内空气质量通风标准，室内PM _2.5监测结果表明，2018年住宅受到严重污染。预计未来会有更多住宅保持室内清洁环境。因此，至关重要的是在建筑设计中考虑室内PM _2.5污染风险，以防止不安全的室内高浓度可能带来的后果。如本文所述，使用此预测模型将提供有关颗粒沉积速率（ K）和渗透系数（ P）对室内PM _2.5浓度影响的更多信息。